Strike off beam and spreader plow assembly for placer spreader

ABSTRACT

In combination with a placers/spreader having a frame including at least two side bolsters standing parallel to the subgrade path and at least two cross beams spanning the subgrade path forming a conveyor supporting structure. A rail system is attached spanning the frame, and has a roll in/roll out conveyor with a cantilevered support at one of the side bolsters and a support for attachment to and support from the rail system. The conveyor moves in traversing motion across the frame to distribute concrete. The improvement comprises a strike off beam and spreader plow assembly for trailing attachment to the frame of a placer/spreader. We thus disclose a strike off beam with spreader plow assembly which can be removably attached to either side of a placer/spreader to avoid the necessity of relocating the receiving conveyor when the location of the access road changes from one side to the other or direction of spreading changes. We additionally disclose a method of operation the strike off beam from a placer/spreader to prevent the accumulation of excess concrete the path of the following paver.

CROSS-REFERENCES TO RELATED APPLICATIONS

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STATEMENT AS TO RIGHTS TO INVENTIONS MADE UNDER FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

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REFERENCE TO A “SEQUENCE LISTING,” A TABLE, OR A COMPUTER PROGRAM LISTING APPENDIX SUBMITTED ON A COMPACT DISK.

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BACKGROUND OF THE INVENTION

This invention relates to a strike off beam and spreader plow assembly which can alternately be placed and supported spanning a subgrade to be paved behind a placer/spreader. More particularly, mounts are provided to removably mount the strike off beam and spreader plow on either spanning side of the placer/spreader to permit the loading of concrete from either side of the placer/spreader. The mounts permit rapid transfer of the strike off beam and spreader plow assembly to edges of the placer/spreader to enable the placers/spreader to receive concrete from access roads on opposite sides of a subgrade being paved.

Slipform pavers are commonly utilized for paving reinforced and non-reinforced concrete roadways and airfield pavements. It is common practice for the concrete delivery trucks to back up on the subgrade and dump the contents of the truck on the subgrade in the path of a slipform paver and thereafter slipform the placed concrete into the final profile of the specified concrete slab section. However, in some cases it is not possible for the trucks to drive on the subgrade of the roadway in the path of the slipform paver and a separate access road must be employed along side the road. In this case a placer/spreader can be utilized.

Access roads are required along the road subgrade when the subgrade in front of the slipform paver is not suitable for driving and dumping (such as when the subgrade is extremely porous for example where superior drainage under the placed pavement is desired) or too soft thus not supportive enough for the delivery trucks. Placer/spreaders are also utilized to receive and distribute concrete over the top of pre-placed dowel basket assemblies or chaired continuous reinforcing bar reinforcement secured to the subgrade that would otherwise block the path of the concrete delivery trucks.

Slip form pavers having roll in/roll out conveyors require occasional disassembly. Specifically, where the access road is moved from one side of a paving path to an opposite side of the paving path, it is necessary to reverse the conveyor and to telescope the conveyor to the opposite side of the placer/spreader. This requires removing the conveyor from its supporting frame, reversing the conveyor end for end, and reinstalling the conveyor to telescope into and out of the opposite side of the supporting frame.

In the mid-1960s, CMI Corporation (originally Construction Machinery Inc.) of Oklahoma City, Okla. manufactured a placer/spreader known as the PST 400 having the above construction with a roll in/roll out conveyor belt. Since then, another manufacturer copied this machine in its entirety. The machine included a main tractor frame with two side bolsters supporting an underlying concrete spreader auger with strike-off and an attached overlying power unit. The main tractor frame had an attaching rear bolster. Attached to the front of the main tractor frame was a conveyor supporting frame (conveyor module) which had an underlying roll in, roll out conveyor and an attaching front bolster. The entire assembly was supported on four jacking columns with crawler tracks. Where the access road changed sides on the paving path, conveyor disassembly was required.

Additionally, this machine had superior function and productivity but was bulky, requiring multiple loads to be transported between job sites.

Specifically, three discrete loads are required to transport it. Further, both assembly and disassembly of the unit requires a crane assist. Regarding the loads, a first load includes the main tractor frame with power unit and underlying spreader auger assembly. A second load includes the conveyor-supporting frame with underlying roll in, roll out conveyor. A third and final load included the disassembled front and rear bolsters each with jacking column and supporting crawler track. Disassembly and assembly of the placer/spreader was and is very time consuming taking days to set up and tear down.

Moreover, the two discrete frames, namely the conveyor support frame and tractor frame, required re-sectionalization when a width change of the placer spreader is required say to change the width from a standard 24 ft. wide pavement to a 30 ft. wide pavement.

This machine utilized spreader augers. It should be understood that spreader augers utilized by the prior art are less than optimum. Typically, and because of the limits of the auger flighting and the mass of the auger, a central support bearing is required to support the auger from the main tractor frame. The supported auger includes opposed auger flights terminated at the central bearing. Further, such augers have a diameter in the range of three feet in order to be large enough to spread concrete rapidly. Finally, and assuming that more concrete is placed on one side of the auger support bearing than on the other side of other support bearing, redistributing concrete across the central support bearing of the spreader auger is problematic at best. Furthermore, spreader augers are very costly to operate because of the auger flighting and bearings wears out rapidly when conveying abrasive concrete.

In combination with a placers/spreader having a frame including at least two side bolsters standing parallel to the subgrade path and at least two cross beams spanning the subgrade path forming a conveyor supporting structure. A rail system is attached spanning the frame, and has a roll in/roll out conveyor with a cantilevered support at one of the side bolsters and a support for attachment to and support from the rail system. The conveyor moves in traversing motion across the frame to distribute concrete. The improvement comprises a strike off beam and spreader plow assembly for trailing attachment to the frame of a placer/spreader. The placer spreader has a strike off beam spanning the frame, and first and second of attachment points on either side of the frame, the attachment points for mating with the attachment bars of the strike off beam. Attachments on the strike off beam attach to either of the first and second attachment points on opposite sides of the frame. A spreader plow track is attached at the upper surface of the strike off beam; and has a spreader plow car movable along the spreader plow track from side to side of the strike off beam. A spreader plow is dependently mounted from the spreader plow car for plowing concrete side to side in advance of the strike off beam. The improved spreader plow and strike off beam can be reversibly mounted to either side of the machine to enable reversing of machine direction without conveyor disassembly.

We thus disclose a strike off beam with spreader plow assembly which can be removably attached to either side of a placer/spreader to avoid the necessity of relocating the receiving conveyor when the location of the access road changes from one side to the other or direction of spreading changes. By disclosing this detachable assembly, we disclose the strike off beam and spreader plow assembly which can be used on either side of placer/spreaders. The prior art has failed to recognize that such a removably attached assembly can have this utility.

We avoid the necessity of relocating the receiving conveyor when the location of the access road changes from one side to the other or direction of spreading changes. Relocating the receiving belt is extremely time consuming as opposed to relocating the strike-off beam with spreader plow. Furthermore, by using a spreader plow as opposed to an auger in conjunction with the strike-off beam, the spreader plow with strike-off can be retracted close enough to the tractor frame that the strike-off does not require separate removal for transport.

We additionally disclose a method of operation the strike off beam from a placer/spreader to prevent the accumulation of excess concrete the path of the following paver.

BRIEF SUMMARY OF THE INVENTION BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A is a perspective view of the strike off beam and spreader plow—separate and apart from either a placer/spreader or a paver—illustrating the strike off beam in an extended working position with a spreader plow operating from a positioning overlying the strike off beam to spread concrete immediately before contact with the strike off beam;

FIG. 1B is a perspective view of the strike off beam and spreader plow—separate and apart from either a placer/spreader or a paver—illustrating the strike off beam in a collapsed transport position with a spreader plow stowed overlying the strike off beam for nesting immediately adjacent a paver and/or placer/spreader during transport;

FIG. 2 is a perspective view of the strike off beam spreader plow assembly attached at the front of a paver for first spreading of concrete using the plow and second distribution of concrete utilizing the strike off beam;

FIG. 3A and 3B are respective side elevations and plan views of the strike off beam spreader plow assembly attached at the back of a placer/spreader with the spreader plow operative to distribute concrete immediately before concrete distribution and the strike off beam;

FIGS. 4A and 4B are respective elevation and plan views of a placer/spreader disengaged from strike off beam spreader plow assembly;

FIGS. 5A and 5B are respective elevation and plan views of the placer/spreader shown in FIGS. 4A and 4B having the placer/spreader reversed and approaching the strike off beam and spreader plow assembly from the opposite side; and,

FIGS. 6 is an elevation of the placer/spreader shown in FIGS. 5A and 5B having the placer/spreader turned 180 degrees and re-engaged to the strike off beam spreader plow assembly in the opposite direction;

FIGS. 7A and 7B are side elevations of a placer/spreader and paver with a strike off beam spreader plow assembly being utilized to disburse accumulated concrete immediately in front of the paver.

DETAILED DESCRIPTION OF THE INVENTION

Referring to FIG. 1A, the strike off beam and spreader plow assembly 10 is illustrated in perspective. Strike off beam 12 has vertical supports 14 located at either end or side spanning placed concrete 20. Centrally of strike off beam 12 there is placed hinge 18 which is articulated by hydraulic cylinder 19 to apply a berm profile to strike off beam 12.

Vertical supports 14 have longitudinally extending male couplers 16 on either side of strike off beam and spreader plow assembly 10. It is these male coupler 16 which enable engagement of the strike off beam and spreader plow assembly 10 to either side of a placer/spreader.

Support on male couplers 16 is spreader plow assembly 30. Spreader plow assembly 30 includes a spanning rail 31, a spreader plow car 32 which rides rail 31 in spanning movement, and a reel and cable movement system 33 for moving a depending spreader plow 34. When strike off beam and spreader plow assembly 10 is attached to a placer/spreader, plow 34 spreads concrete with side to side movement while strike off beam 12 assures the ultimate profile to the roughly placed concrete for forming into a road profile by a following paver.

At either side mud guards 41, 42 are provided. These mud guards prevent placed concrete from being spread outside of the path of the placer/spreader. It will be noted that mud guard 42 is longer than mud guard 41. This is because mud guard 41 is adjacent the telescoping conveyer of the placer/spreader.

Referring to FIG. 1B, it is necessary for strike off beam and spreader plow assembly 10 to be nested immediately adjacent to the placer/spreader for transport. This being the case, spreader plow 34 is removed from spreader plow car 33. Respective mud guards 41, 42 are disposed inwardly on hinges. Finally, spanning rail 31 is moved immediately adjacent to vertical supports 14. As will hereafter be apparent, nesting of the strike off beam and spreader plow assembly 10 immediately adjacent to a placer spreader can occur. As will become apparent, this nesting will be required for the single trailer transport of the compact placer spreader utilized with this invention.

Referring to FIG. 2, strike off beam and spreader plow assembly 10 is shown in an operating disposition separate from a placer/spreader 40. Placer spreader 40 includes a machinery module 42 supported on a frame F. Telescoping into and out of frame F is belt B, which belt B receives concrete from a dump truck on access road 20 when telescoped out from under frame F. Unfortunately, access roads can change sides relative to the path to be paved. It is this condition that illustrated in FIG. 2. The problem to be solved, is how to accommodate this shift in sides. In FIG. 2, placer/spreader 40 is proceeding upward and to the right. It has reached the end of right side access road 20 and is coming upon left hand side access road 20. Clearly, if belt B telescopes to the same side, it will not be able to gather concrete once right hand access road 20 ends.

The prior art has solved this problem by removing the telescoping belt B from frame F and reversing the belt. This has extreme assembly and disassembly complications. We seek a simpler solution that follows.

Referring to FIGS. 3A and 3B, placer/spreader 40 is shown respectively in side elevation with large single crawler 51 having two jacking columns 52 blocking an end of frame F. Strike off beam and spreader plow assembly 10 is conventionally attached at male couplers 16 penetrating interior of female couplers 26 carrier on placer/spreader 40. Referring specifically to FIG. 3B, it will be seen that belt B telescopes out of frame F to the upper portion of the plan view shown.

Referring to FIGS. 4A and 4B, male couples 16 having been disconnected (typically by the removal of pins) from female couples 26 in placer/spreader 40. Placer/spreader 40 has been allowed to freely stand on strike off beam 12 and spreader plow 42. In the view shown, strike off beam and spreader plow assembly 10 is now a free standing unit complete detached from placer/spreader 40.

Referring to FIGS. 5A and 5B, spreader/placer 40 has been driven away and turned around. Thereafter, it has been returned to confront strike off beam and spreader plow assembly 10 at female couplers 26 opposed to male coupler 16 on strike off beam and spreader plow assembly 10.

Finally, and with respect to FIG. 6, reengagement of placer/spreader 40 with strike off beam and spreader plow assembly 10 is illustrated. Specially, male couplers 16 have penetrated interior of female couplers 26. Belt B now telescopes towards the viewer in FIG. 6 as distinguished from away from the viewer as shown in FIG. 3A. Reversal simply occurs.

Referring to FIG. 7A, an additional feature of strike off beam and spreader plow assembly 10 is illustrated. Simply stated, a paver P is shown pushing a large accumulation of concrete (here shown in the form of a cylinder) ahead of the slip form paver P. This accumulation is a common occurrence where too much material is left in the wake of the placer/spreader 40. Looking further at placer/spreader 40, it will be seen that strike off beam 12 has been used in a bull dozer type function. Specifically, and through the manipulation of jacking columns 52, strike off beam 12 has placed an indentation into the placed concrete. Normally, this indentation would cause an insufficiency in the path of slip form paver P.

Referring to FIG. 7B, it will be seen that slip form paver P has advanced to the depression created by strike off beam 12. The large cylinder of concrete has fallen into this depression. This cylinder of concrete is immediate the path of the slip form paver where it will be shortly slip formed into the profile of the roadway or runway being paved.

It will be understood that the technique illustrated in FIGS. 7A and 7B is a compromise. In actual fact when material is accumulated in front of a slip form paver, some classification of the constituents of the concrete occurs. Accordingly, other measures to improve the quality of the concrete utilized may be taken, such as hand finishing the volume of concrete filled in. 

1. In a frame including; at least two side bolsters standing parallel to the subgrade path and at least two cross beams spanning the subgrade path forming a conveyor supporting structure across the span of the frame; a rail system attached to and spanning the frame; and, a roll in/roll out conveyor having a cantilevered support at one of the side bolsters and a support for attachment to and support from a rail system in traversing motion across the span of the frame; the improvement comprising a strike off beam and spreader plow assembly for attachment to the frame of a placer/spreader comprising: a strike off beam spanning the frame; first and second of attachment points on either side of the frame, the attachment points for mating with attachment bars of the strike off beam; attachment bars on the strike off beam for attachment to either of the first and second attachment points on opposite sides of the frame; a spreader plow track attached at the upper surface of the strike off beam; a spreader plow car movable along the spreader plow track from side to side of the strike off beam; a spreader plow dependently mounted from the spreader plow car for plowing concrete side to side in advance of the strike off beam; and, means for moving the spreader plow car from side to side to enable the spreader plow to spread concrete in advance of the strike off beam.
 2. The strike off beam and spreader plow assembly for attachment to the frame of a placer/spreader or paver having attachment points according to claim 1 and further including: the strike off beam spanning the frame is expandable to enable accommodation of the strike off beam and spreader plow assembly to frames having varying widths.
 3. The strike off beam and spreader plow assembly for attachment to the frame of a placer/spreader or paver having attachment points according to claim 1 and further including: means mounted between the attachment beams and the strike off beam for enabling the strike off beam to be supported at varying elevations relative to the attachment bars.
 4. A process for the reversible mounting a strike off beam and spreader plow assembly to the frame of a placer/spreader at an access road on one side of the subgrade to be paved to an access road on the opposite side of the subgrade to be paved, the process comprising the steps of: providing a placer/spreader for receiving already mixed concrete at an access road adjacent to the subgrade at a conveyor disposed to one side of the subgrade to be paved and moving the conveyor to distribute the received concrete along the path to paved; providing the frame of placer/spreader with attachment points spanning the frame on either side of the frame; providing a strike off beam spanning the frame; providing a spreader plow mounted to the strike off beam for moving side to side relative to the strike off beam to displace concrete from side to side of the strike off beam; providing attachment bars at either end of the strike off beam for attachment to the attachment points spanning the frame; attaching the attachment bars the attachment points on one side of the frame to support the strike off beam and spreader plow assembly from the frame; supporting the strike off beam and spreader plow assembly from the subgrade; detaching the attachment bars on the one side of the frame; reversing the frame of the placer/spreader to address the attachment points on the other side of the frame to the attachment bars; and, attaching the attachment bars the attachment points on the other side of the frame whereby the conveyor disposed to one side of the subgrade to be paved is reversed to the opposite side of the subgrade to be paved at an access road adjacent to the subgrade.
 5. (canceled) 